The ability to monitor and detect vibrations originating in different parts of various kinds of equipment such as reciprocating engines, gas turbines, compressors, electric motors and generators, etc. is useful in a number of ways. A device with this capability is useful, for example, in the routine inspection of such equipment during initial qualification testing at the end of an assembly line. It may also be used as a means for diagnostic testing as an aid in the determination of the source of a mechanical or electrical malfunction. There are also applications for devices of this type in which it is appropriate to provide continuous monitoring of specific parts or elements of a critically important system in order to have advance notice of impending mechanical problems so that appropriate corrective action may be taken to prevent a malfunction.